The field of the invention relates to electrical motors and more particularly to induction motors.
Induction motors, such as squirrel cage induction motors, are in common use. Such motors, because of their simplicity and reliability, are one of the most widely used electric motors in use today.
While squirrel cage induction motors are cheap and effective, the rotor windings on such motors are often difficult to manufacture. In order to function properly, the windings of the rotor must be insulated from the underlying rotor laminations. Where the winding insulation is insufficient, the windings may short to the lamination and, ultimately, to each other. Such shorting leads to a reduction of efficiency and ultimately to failure of the motor. Because of the importance of squirrel cage motors a need exists for a means of evaluating the insulation quality of the rotor.